It looks like the "potato masher"

I've been meaning to run this badly scanned image for some time. It's a Rebel hand grenade and appears in Never for Want of Powder. The pressure detonator has been withdrawn and is the pin-type of assembly to the left. In the German stick grenades, the detonator was the entire head assembly.

Unlike the "infernal devices" left at Yorktown, this model was designed to be thrown. Interesting that each one comes with a canvas strap attached.